机制砂混凝土在南水北调东线穿黄河工程中的应用

The Application of the Machine-made Sand Concrete in the the Yellow River through Eastern South-to-north Water Diversion Project

随着我国基础设施建设的迅猛发展和对环境保护的日益重视,天然砂将逐步减少开采,其可利用数量已经远不能满足工程建设的需要,大量使用机制砂配制混凝土已成为必然趋势。在国家重点工程南水北调东线穿黄河工程中,采用机制砂混凝土,优化配合比,研究制备出了符合工程技术要求的高性能混凝土。经对比分析,不仅部分技术指标优于天然砂混凝土,而且质量稳定、价格较低,既满足了工程需要,又节约了工程投资。文章结合工程实际,对机制砂制备的原料选择、生产工艺、技术要求、质量检验与控制、经济指标等进行了分析论证,针对我国存在多种机制砂混凝土的地方和行业标准问题,提出了制订统一完善的机制砂混凝土技术标准体系的建议;提倡在混凝土制备环节搞好机制砂混凝土配合比优化研究,制备出耐久性更好的高强度混凝土,以满足工程建设需要。

With the rapid development of infrastructure construction in China and much concern with environmental protection, there is a gradual decrease in mining natural sand and its available quantity doesn＇t satisfy the demand of projects, so it is an inevitable trend to use a great deal of machine-made sand concrete. In the process of building the national key projects --the Yellow River through eastern South-North Water Diversion Project, by using machine-made sand concrete and the optimal mix proportion, a kind of high-performance concrete is excogitated. By contrasts and analyses , we find that some of the technical indexes are not only better than those of natural sand concrete but also have stable quality, lower prices. What＇s more, it gives us a chance to meet the needs of the project. Research is done on prepared materials made of machine-made sand, production process, technical requirements, quality inspection and control and economic indexes based on practical construction. Considering that there are many local standards in China, suggestions are made about a unified and perfect system of technical indexes. In the process of preparing concrete, research is done on optimization of mix proportion of machine-made sand concrete to satisfy the engineering constructions demands.